Element story

Mendelevium

Atomic number 101 means that every Mendelevium nucleus contains 101 protons. That proton count is the element's identity: change it and you no longer have Mendelevium.

Start with the nucleus

Atomic number 101 means that every Mendelevium nucleus contains 101 protons. That proton count is the element's identity: change it and you no longer have Mendelevium.

Mendelevium (Md) is chemical element 101. It belongs to the actinoids, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.

In practice, it turns up most often in scientific research.

See the atom

Conceptual visual: electron shells are a learning aid, not a literal picture of quantum orbitals.

What this number means

Atomic number 101 means that every Mendelevium nucleus contains 101 protons. That proton count is the element's identity: change it and you no longer have Mendelevium.

Keep exploring

→ Mendelevium · Atomic structure · Periodic trends

Sources

EN · institutional/academic · IUPAC · CIAAW · NIST